Aguilera got so thin she fueled rumors she had an eating disorder or had gotten weight-loss surgery.

The blonde beauty vehemently denied those reports, and insisted she lost weight by following a low-carb diet and doing yoga.

In May 2008, Aguilera lost 40 pounds just four months after giving birth to son Max by combining fat-burning cardio workouts and weight-lifting for 90 minutes a day, five days a week, and following a low-carb diet.

While Christina isn’t a workout fanatic, she said exercising made her feel and look great.

“I feel a sense of accomplishment,” Christina said. “As you feel your body getting stronger, you become more motivated to be in the gym!

“It doesn’t matter how big or small you are. When you’re defined, it’s sexy. I exercise because it makes me feel good. It’s not just a physical thing.”